I WAS 12 when I went to Disneyland — the original one, in California, where orange groves once flourished — but for the next 37 years I have not been to another big theme park.

Don’t get me wrong: Disneyland did not scar me or anything. In fact, my diary at the time reports it was “a blast”. It’s just that as an adult, I saw no reason to pay to make myself dizzy. My children have been to theme parks, just not with me.

Disneyland is now 50 and, when I was asked to return to write about how it had changed, I admit that I felt no joy, only a curiosity about how awful it would be (there were tales of queues as long as the Nile). But my daughter Gillian, who is 22 and possibly deeply scarred from our lack of theme-park bonding, was thrilled. “Disneyland!” she cried. “I’m so excited!”

I stayed quiet, as I have been told that being a total Eeyore all the time can be very irritating. Inwardly, of course, I anticipated the worst. In 1968 Disneyland had seemed magical, a place of pirates and hippos, of hot fudge sundaes and banana splits, of giant Mickeys and Plutos. But I was sure that, in the intervening years, rampant commercialism would have changed all that at what Disneyland calls “The Happiest Place on Earth”.

We were hot and sweaty, but definitely not happy, on arrival at our hotel. This was the Grand Californian, which is run by Disney and is inside the extended park. In fact, it is more of a lodge and indeed a grand one, decorated rather tastefully in Arts and Crafts style. In our room, we were welcomed with milk and triple chocolate cookies. It sounds like something out of the Waltons, but the offerings were so huge and scrumptious that we did not care.

Early the next morning (no one sleeps in at the Happiest Place) we left our room to find a family in the hallway preparing for their Disney day. It was a military operation, with two pushchairs so large that they could be mistaken for Humvees. Their daughter, who was about five, had on a long yellow princess costume with a tall pointed hat complete with veil. Somehow she had managed to stick Mickey Mouse ears on to the sides of the hat. Her eyes were like saucers and she was too excited to speak.

Chip ’n’ Dale (for those readers who do not know these things, this is not a male stripper troupe but two giant chipmunks) were romping around at breakfast. Children, almost all wearing Mouse ears of some kind, held out their autograph books. Parents took photos, and critters gave hugs.

At some point, a man dressed as a park ranger started to sing: “If you are happy and you know it, clap your hands.” I know, I know. It sounds awful. But, against all odds, I couldn’t help but notice that I was smiling. Not one child was misbehaving: this was their world and the grown-ups were just passing through.

The magic was shining out of their faces and, I suppose that, in 1968, it must have shone out of mine too. I can remember the awe I felt at meeting Goofy, my favourite. For me, now, that trip is infused with memories of my family, and particularly my father, who died 28 years ago.

The first thing I spotted when I got out my scrapbook (I was a maniac about chronicling our holidays) was my father’s handwriting on our Disney tour tags. It was a shock, for grief retains the power to ambush, even after all this time.

It was a short walk from the Grand Californian to the turnstile entrance. The inclusive price for the day is £33 for adults, £27 for children. (In 1968 it was £3.40 and £2.80.) There was, of course, a queue. It was already 32C (90F). Once inside, a woman barked at me for accidentally barging into her family photo in front of the Mickey flower clock. Then, even more unhappy than usual, my daughter and I entered Disneyland, under a sign that said: “Here you leave today and enter the world of yesterday, tomorrow and fantasy.”

In front of us was an old-fashioned American Main Street. There was a marching band in all-white costumes, epaulettes a-go-go, and a horse-drawn streetcar. We clambered on. The horse was named Barney and his driver was Stefanie. There was a kerfuffle as Minnie was spotted on the pavement. So tiny! With so many polka dots! A rumour began that Mickey might be near by.

“But is there only one Mickey?” I asked Stefanie.

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